This invention relates to pull pieces or pull tabs adapted to be removably attached to the lids of various cans containing refreshing drinks for readily opening the cans allowing the user to drink the contents.
Most conventional cans containing refreshing drinks have a pull piece or pull tab 20 removably attached by means of a rivet 18 to an opening piece 15 defined by a cut line or score 16 provided on the lid 10 of a can, as shown in FIG. 7, which allows for removal of the opening piece 15 by pulling the pull tab 20 up, thus enabling the user to drink the contents of the can.
As shown in FIG. 8, the conventional pull tab 20 integrally comprises a panel portion 25 having a rivet hole 26 therein, left-and right-hand leg portions 22, 22 formed on and connected to the opposite sides of the panel portion 25 by means of an intermediate semi-circular ramp and a ring portion 21 contiguous to the ends of the leg portions 22, 22 and remote from the panel portion 25.
The inner peripheral edge of the ring portion 21 is folded back outwardly to form an inner peripheral fold-up 31 and the outer peripheral edge of the ring portion 21 is also folded back inwardly in the opposite direction from the inner peripheral fold-up 31 to form an outer peripheral fold-up 32. The outer side edges of the left- and right-hand leg portions 22, 22 are also folded back inwardly or in the same direction as the outer fold-up 32 of the ring portion 21 to form side edge fold-ups 33, 33 which are contiguous to the outer fold-up 32 at the outer peripheral edge of the ring portion 21.
When the inner and outer peripheral fold-ups 31, 32 of the ring-portion 21 and the outer side edge fold-ups 33 of the leg portions 22 are formed by folding the blank for the pull tab 20, the severed edges of the pull tab 20 which remain sharp as the blank of the pull tab is stamped out of a piece of sheet metal are rounded, as shown in FIG. 9, whereby the pull tab providds a safeguard to the user and rigidity is imparted to the pull tab.
However, in order to impart the pull tab 20 with a rigidity sufficient for tearing the opening piece 15 off the can lid 10 so as to allow the contents of the can to be drunk the conventional pull tab 20 has to be formed of thick sheet metal having a thickness on the order of 0.36 mm, which makes it difficult to reduce the thickness of the pull tab as desired.